The Molecular Biology/Gene Expression Core Facility will provide two critical services to support the scientific goals of this Program Project, namely a digestive disease reagent bank and a gene expression facility, both of which will be focused towards esophageal cancer research: 1. Digestive disease reagent bank: Each of the Program Project Leaders and their personnel have access to specific plasmids, expression constructs, reporter constructs, antibodies, RNA samples, and retroviral/adenoviral vectors that are relevant to the study of esophageal biology as it relates to carcinogenesis. As a result, these reagents have been organized and centralized. In addition, we will continue to store newly available reagents. One of the technicians is responsible for the acquisition, maintenance and distribution of these reagents. Nearly all the reagents provided by this bank are unique reagents that are not available commercially. For example, a common commercial source for reagents, ATCC, does not provide antibodies, RNA samples, or retroviral vectors. Furthermore, less than 10% of the cDNAs/expression vectors in the digestive disease reagent bank are available through ATCC. Tissue procurement, storage and RNA extraction will be centralized with the Morphology Core, and a database will be maintained. 2. Gene expression facility: The ability to examine and quantify alterations in gene expression in fundamental to the understanding of molecular mechanisms that determine biological processes. High density gene arrays are now a technical reality. The cost of this technology, although previously prohibitive for most investigators, has very recently become affordable. This facility has 2 components: 1) arrays: both digestive organ custom arrays and Affymetrix commercial arrays; and, the Genomax bioinformatics workstation, and 2) Real-time Quantitative PCR. The gene expression facility will be highly interactive, providing opportunities for the members of this Program Project to interact at multiple levels. Examples of these interactions include but are not limited to the following: 1) facilitate the analysis of wildtype and genetically engineered mice; 2) complement the analysis of gene expression performed by the Morphology Core through in situ hybridization; and 3) assist in the analysis of cell culture model systems.